I have to get the IDENTITY values from a table after SQLBULKCOPY to the same table. The volume of data could be thousands of records.
Can someone help me out on this ?
I have to get the IDENTITY values from a table after SQLBULKCOPY to the same table. The volume of data could be thousands of records.
Can someone help me out on this ?
Disclaimer: I'm the owner of the project Bulk Operations
In short, this project overcomes SqlBulkCopy limitations by adding MUST-HAVE features like outputting inserted identity value.
Under the hood, it uses SqlBulkCopy and a similar method as @Mr Moose answer.
var bulk = new BulkOperation(connection)
// Output Identity Value
bulk.ColumnMappings.Add("CustomerID", ColumnMappingDirectionType.Output);
// Map Column
bulk.ColumnMappings.Add("Code");
bulk.ColumnMappings.Add("Name");
bulk.ColumnMappings.Add("Email");
bulk.BulkInsert(dt);
EDIT: Answer comment
can I simply get a IList or simply , I see its saved back in the customers table, but there is no variable where I can get a hold of it, can you please help with that. So, I an insert in Orders.CustomerID table
It depends, you can keep a reference to the Customer DataRow named CustomerRef
in the Order DataTable
.
So once you merged your customer, you are able to populate easily a column CustomerID
from the column CustomerRef
in your Order DataTable.
Here is an example of what I'm trying to say: https://dotnetfiddle.net/Hw5rf3
I've used a solution similar to this one from Marc Gravell in that it is useful to first import into a temp table.
I've also used the MERGE
and OUTPUT
as described by Jamie Thomson on this post to track data I have inserted into my temp table to match it with the id generated by the IDENTITY column of the table I want to insert into.
This is particularly useful when you need to use that ID as a foreign key reference to other tables you are populating.
Try this
CREATE TABLE #temp
(
DataRow varchar(max)
)
BULK INSERT #Temp FROM 'C:\tt.txt'
ALTER TABLE #temp
ADD id INT IDENTITY(1,1) NOT NULL
SELECT * FROM #temp
-- dummy schema
CREATE TABLE TMP (data varchar(max))
CREATE TABLE [Table1] (id int not null identity(1,1), data varchar(max))
CREATE TABLE [Table2] (id int not null identity(1,1), id1 int not null, data varchar(max))
-- imagine this is the SqlBulkCopy
INSERT TMP VALUES('abc')
INSERT TMP VALUES('def')
INSERT TMP VALUES('ghi')
-- now push into the real tables
INSERT [Table1]
OUTPUT INSERTED.id, INSERTED.data INTO [Table2](id1,data)
SELECT data FROM TMP